Optimal possibilistic-robust operation of multi-energy microgrids considering infrastructure hydrogen storage capability

Abstract

In sustainable energy transitions, the utilization of hydrogen is crucial, providing flexibility in the operation of net-zero emission renewable-based energy systems. This paper presents a study on the optimal operation of net-zero emission multi-energy future microgrids that utilize hydrogen as an alternative fuel instead of natural gas. The electrolyzers' output is injected into the hydrogen grid to meet demand or converted back to electricity later using generating units, owing to the storage capability of pipes, called linepack. For this purpose, a detailed mathematical model is developed to simulate the main characteristics of grids (e.g., voltage, current, hydrogen flow, and pressure) as well as various components (e.g., renewable systems, electrolyzers, and hydrogen-fired units). To become more realistic, a possibilistic-robust approach is developed to account for the uncertainty arising from the lack of real-world implementation. By representing a case study, a test is performed to evaluate the possibility of employing a low-pressure gas grid to meet the demand for hydrogen. After that, the effects of electrolyzers are analyzed in the presence and absence of the uncertainty consideration approach. The result indicates that, despite hydrogen's lower energy density compared to natural gas, it is still feasible to satisfy the same energy demand level, considering the technical characteristics of the grid. The integration of electrolyzers can reduce wind curtailment by 2 % and supplement hydrogen demand by 50 %. A higher level of conservatism in the possibilistic-robust approach leads to an increase in the mean value of the objective function and a reduction in the standard deviation under the realization of uncertain parameters, which provides the decision-makers with a more realistic insight.